设置SMTP deliveryMethod时出错

Had*_*ati 0 c# asp.net web-config smtpclient

嗨,这是从IIS发送电子邮件的一段代码,但我收到此错误
无法解析属性'deliveryMethod'的值.错误是:SmtpDeliveryMethodTypeConverter无法从System.String转换

这是我的代码:

MailMessage message = new MailMessage  ("mostang1970@yahoo.com", "hadinematipartow@yahoo.com");
message.BodyEncoding = System.Text.Encoding.UTF8;
message.SubjectEncoding = System.Text.Encoding.UTF8;
message.Subject = "testing of mailing list";
message.Body = "hi hadi .this email is just for test.";
message.IsBodyHtml = true;

SmtpClient smtpClient = new SmtpClient("127.0.0.1");
smtpClient.DeliveryMethod = SmtpDeliveryMethod.PickupDirectoryFromIis;
smtpClient.Send(message);
Run Code Online (Sandbox Code Playgroud)

这是我的web.config:

<system.net >
    <mailSettings >
      <smtp deliveryMethod="PickupDirectoryFromIis " >
        <network host ="localhost" port ="25" defaultCredentials ="true "/>
      </smtp>
    </mailSettings>
   </system.net>
Run Code Online (Sandbox Code Playgroud)

请帮忙

Dia*_*o25 5

之后有一个空格deliveryMethod="PickupDirectoryFromIis,您可能想删除它.